In Finnic languages, such as Finnish and Estonian, this case is often used to express unknown identities and irresultative actions.
For example, in Finnish, it is found in the following circumstances, with the characteristic ending of -a or -ta: Where not mentioned, the accusative case would be ungrammatical.
In Estonian grammatical tradition, the term "accusative" is not used, since like in Finnish, the total object form coincides with the genitive in the singular, and the nominative in the plural.
For many verbs in Estonian, an additional adverb is almost always added when a completed action is meant - for example, ma söön leiba "I'm eating bread", vs ma söön leiva ära "I will eat the (whole) bread".
Since Estonian, unlike Finnish, has words where the genitive and partitive singular are identical even in pronunciation, this can provide disambiguation in those cases - e.g ma söön kala "I'm eating fish", vs ma söön kala ära "I will eat (all of) the fish".
The partitive variant is preferred with verbs: выпить чаю, výpit' cháyu, "to have a drink of tea".
The genitive variant is used more frequently when the mass noun is modified by an adjective: чашка горячего чая cháshka goryáchevo cháya, "a cup of hot tea".